Scattering scanning near field optical microscopy (s-SNOM) operates by interacting a sharp probe tip of a probe microscope with a sample surface and collecting light scattered from the region of tip-sample interaction. Using this technique, it is possible to measure the optical properties of samples with a spatial resolution far below the conventional diffraction limits. The resolution improvement comes from a local enhancement of the incident radiation field due to the sharp tip. The enhanced radiation field interacts with the sample and then scatters radiation into the far field. This near-field enhancement increases the amount of radiation scattered from the tip-sample region such that the scattered radiation can be more easily detected from nanoscale regions of a sample. Atomic force microscope based infrared spectroscopy (AFM-IR) provides chemical characterization and compositional mapping on nanometer length scales by using the tip of an atomic force microscope to locally detect absorption of infrared radiation.